When the dental organ is damaged, the role of the dental surgeon is to restore it.
When there is significant decay, this restoration calls upon prosthetic devices that replace all or part of one or more of the teeth concerned.
This cannot be done without taking into consideration dental occlusion, which is the manner in which interdental and interarch contacts are organized.
In this context, the management of interdental contacts is a therapeutic imperative.
Furthermore, other situations exist in which the management of dental contacts is a therapeutic imperative.
For example, when the teeth are in ectopic position, an orthodontic treatment is undertaken in such a way as to displace the teeth thanks to an apparatus. The configuration and the distribution of the occlusal contacts change and rules need to be respected in this case so as not to harm the patient.
In other cases, when disorders of the joint or muscular contraction are diagnosed and have a relation with occlusion, the dental surgeon may, through the design of an occlusal mouth guard, attenuate or even correct these dysfunctions.
By extension, occlusion ensures the interface between the two maxillaries. Their confrontation is possible thanks to a moveable bone: the mandible (lower maxillary).
The quality of this occlusion is vital and has to assure three essential functions (centering; bracing; guiding) of this same mandible in order to preserve the surrounding structures (joint, muscles, etc.).
The motility of the mandible is due to a joint, the temporomandibular joint (TMJ) and a setting in motion by the contraction of the mastication muscles.
At all times, the dental surgeon is concerned with preserving the good health of these components but also its re-establishment when pathologies are objectivized (such as myalgia, arthropathy). In this case, the dental surgeon may, through rehabilitation of the occlusion, have a retroactive effect on pathologies of the manducatory apparatus.
The construction or reconstruction of the occlusion is under the influence of certain determinants, which are data linked to the patient having an influence on the occlusal anatomy.
These determinants are important to apprehend in certain situations because the prosthesis technician, by managing them, draws inspiration from them to model the occlusal surface of the teeth.
The determinants of occlusion are factors that influence occlusion. These factors are divided into two groups: fixed determinants and determinants capable of being modified by remodeling or repositioning of the teeth.
Modifiable determinants are:                the shape of the teeth (height of the cusps, depth of the fossa, etc.)        the position of the teeth,        the vertical dimension,        the occlusal curves.        
Fixed determinants are:
(1) the vertical and horizontal positioning of the arches with respect to the posterior determinant,
(2) the condylar spacing
(3) the anteroposterior positioning of the arches with respect to the articular posterior determinant,
(4) the articular posterior determinant, which is defined by:                the condylar slope        the Bennett angle        the initial Bennett movement.        
These fixed and modifiable determinants are interdependent of each other.
The modifiable determinants are those on which the dental surgeon concentrates his/her diagnosis and rehabilitation work. To perfect the diagnosis and thereby ensure optimum rehabilitation for the patient, a study of the fixed determinants and the interdependences between the fixed and modifiable determinants is necessary.
To this end, there exists on the market tools known as articulators which simulate more or less well the physiology of the manducatory apparatus.
These articulators are commercially available in mechanical or digital form. These simulators reproduce mandibular kinematics making it possible to take into account the fixed determinants in the diagnostic analysis. The parameterization of these simulators is carried out by using approximations of the fixed determinants 2, 3 and 4. The anatomy of the temporomandibular joint is simulated thanks to an addition of angular values schematizing the courses of the mandibular condyle in space. This is parameterized mechanically at the level of the condylar boxes of the simulator.
However, due to their design and their mode of operation, the simulators are a source of errors. In addition, they only enable an approximate management of the determinants, and at the price of tedious programming and costly handling at the dental surgery. Moreover, the mandibular kinematics recreated from these simulators are only an approximate reproduction of the real mandibular movements.
A direct consequence is the outsourcing to a prosthetist of this task, which is nevertheless decisive because it guarantees a prosthetic treatment that is reliable, comfortable and durable.
Document WO 2013/030511 describes a method for designing a dental appliance that implements a recording of the mandibular kinematics of the patient.
This method firstly comprises either obtaining a volumetric image of the facial skeleton by a tomodensitometry technique, or determining reference planes of the facial skeleton by pinpointing points of interest on the face of the patient.
Furthermore, three-dimensional models of the dental arches of the patient are obtained. Said models, positioned with respect to each other during their creation, are registered with the volumetric image of the facial skeleton or the reference planes determined beforehand.
Recording the mandibular kinematics is implemented by equipping the patient with a marker fixed on the forehead of the patient and markers fixed directly on the teeth of the mandibular arch or on the mandible through the intermediary of a support, and by detecting and recording the displacements of said markers by means of a camera during mandibular movements of the patient.
However obtaining elements making it possible to position the models of the dental arches with respect to each other still needs to be improved. In fact, tomodensitometry assumes exposing the patient to X-rays and it is sought to minimize exposure of the patient to such rays.
With regard to the alternative solution consisting in determining the reference planes of the facial skeleton, it requires a certain number of manipulations by the practitioner to point at the different points of interest.